Control valves are used in hydraulic systems of mining machines for example for controlling flow of pressure fluid. One type of such a control valve is a sleeve-like valve comprising at least one opening all the way through the wall of the control valve, and provided in the work chamber of the percussion piston in such a way that the position of the percussion piston affects the flow of the pressure fluid through the at least one opening. When such opening enables or disables the flow of the pressure fluid to a discharge channel and to a tank, cavitation damages may occur on the inner surface of the sleeve-like valve on the side opposite to the opening through which the pressure fluid flows. Additionally, cavitation may cause chipping of the control valve and these metal chips may cause damages in the hydraulic system, such as seizing of parts and components.